Machine for molding concrete blocks.



W. GRAF & C. F.'NICKEL. MACHINE FOR MOLDING CONCRETE BLOCKS.

APPLICATION FILED MAY I6. I917.

1,238,132. PafentedAug. 28,1917.-

3 SHEETS-SHEET I.

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$3 armww W. GRAF & C. F. NICKEL.

MACHINE FOR MOLDING CONCRETE BLOCKS.

APPLICATION FILED MAY I6. I9I7.

Patented Aug. 28, 1917.

a SHEETS-SHEET 2.

W. GRAF & C. F. NICKEL.

MACHINE FOR MOLDING CONCRETE BLOCKS.

APPLICATION FILED MAY16.1917- WILLIAM GRAF AND CHARLES F. NICKEL, OF BALTIMORE, MARYLAND.

MACHINE FOR MOLDING CONCRETE BLOCKS.

Specification of Letters Patent.

Patented Aug. 28, 1917.

Application filed May 16, 1917. Serial No. 169,042.

To all whom it may concern:

Be it known that we, YVILLIAM GRAF and Crmnnns F. NICKEL, citizens of the United States, and residents of Baltimore, in the State of Maryland, have invented certain new and useful Improvements in Machines for Making Concrete Blocks, of which the following is a specification.

This invention relates to machines for molding blocks of concrete and similar ma terial, and more particularly machines for molding hollow blocks; it comprises the combination with a mold and a plunger for compressing the material in said mold, of cores in said mold which are extensible and contractible in the direction in which the plunger moves and which are also movable as a whole in the same direction; it also comprises means for extending and moving said cores and means for holding them in their extended position until the compressing movement of the plunger causes them to contract; it further comprises certain novel features of construction and arrangements of parts, all as more fully hereinafter set forth and as claimed.

In the molding of hollow blocks of concrete or similar material in the manner described in our Patent No. 1,142,696 of June 8, 1915, it has been found that there is sometimes a tendency for the material above the cores to become more densely compacted than the material at the side of the cores. The present invention, which is an improvement on the machine described in our above mentioned patent, is designed to overcome this tendency. This has been effected by the use of extensible cores in the manner more fully described hereinafter.

The present invention is illustrated in connection with the machine described in our above-mentioned patent.

Figure 1 is a side elevation of the molding machine, the upper part comprising the gears for the plunger being omitted;

Fig. 2 is a vertical transverse section on the line 22 of Fig. 1, showing the principal parts of the core actuating mechanism in elevation;

Fig. 3 is a cross section on the line 38 of Fig. 1;

Fig. 4. is a vertical longitudinal section on the line ll of Fig. 2;

Fig. 5 is a vertical longitudinal section through the rear wall of the mold showing the cores in their raised and extended position;

Fig. 6 is a detailed view of the means for holding the cores in their raised and extended position.

The molding machine, which is in general similar to the one described in our abovementioned patent, comprises a base portion 7, supporting columns 8, a vertically movable screw 9 working in a suitable frame member, not shown, and carrying the plunger 10. Uprights 11 move up and down with the plunger and thereby eifect the raising and lowering of the track 12 upon which runs the truck which carries the mold 16, thus permitting the mold to be lowered onto the stationary supporting base 13. The plunger carries a downwardly extending arm 14 adapted, in its downward travel, to move inward the lever 15 and release the catch at the lower end of this lever.

From the rear wall 36 of the mold 16 there extend rods 17, supported at their farther end by braces 18 which extend from the top of the rear wall. Bracket supports 20 carrying the cores 19, are slidably mounted on the rods 17; extending from the bracket supports 20 under the rods 17, are racks 21 meshing with the pinions 22 and serving to draw the bracket supports and the cores out of the mold when the pinions are turned.

The cores 19 comprise vertically telescoping sections 23 and 24 (see Fig. 3) which may be strengthened by suitable cross pieces. The upper section 23 is fastened to an inner core plate 25, the lower section 21 being similarly fastened to the intermediate core plate 26. The core plates 25 and 26 are held against the supporting plate 27 by bolts 28 which extend into slots 29 and 30 in the plates 25 and 26, respectively, thus permitting vertical movement of the plates 25 and 26.

The plate 27 carries at the top an arm 81, at the upper end of which is pivoted a lever 32, the hooked end of which engages a U-shaped member 33 pivoted on the upper edge of the plate 25.

Bolts 34L carried by the plate 26 extend into slots 35 in the plate 25 so as to permit of a limited relative movement between the plates 25 and 26.

The rear wall 36 of the mold is provided with openings 37 of such height as to allow tor the necessary vertical movement of the cores. This wall is also provided with slots 38 for the reception of bolts 39, and slots d0 through which extend the bolts a l. On the inside or the mold is a liner plate ll and an intermediate liner plate 42 which are formed with openings for the cores, the intermediate liner plate also being provided with slots &3 for the reception of the bolts The bolts 3!) which are fastened to the plate 41, and also the bolts 34, have collars surrounding the portion of the bolt which lies in the slot 01": the adjacent plate, the collars being held in place by nuts on the end of the bolts. The intermediate plate 42 is pulled upward by a spring .115, the lower end of which engages a bolt t l extended from said plate, said springoeing suspended from a projection l6 attached near the upper edge of the wall 36.

On both sides of the mold are cores comprising telescoping sections t? and d8. The upper section at? is fastened by screws to the liner plate 4.1 which extends part way around the sides of the mold; the sections 4-7 are held against the sides of the mold by bolts which extend through slots 51, the lower sections a8 being held by bolts 52 extending through slots 58. The upper section a? has a downward extension 53% carrying a bolt 55 which extends into a. slot in the lower section t8, the length of the slot being such that after the upper section has been raised the correct distance the screw 55 will engage the upper end of the slot a nd move the lower section upward.

The means for holding the cores in their extended positions, shown in detail in Fig. 6, comprises a lever 15 carrying at its upper end a roller 56. The lower end of the lever is formed with a hook 57 which is pressed against the core plate by a spring 58 and is adapted to engage the finger 59 which is held in place by screws 60 passing through a slot 61 in the plate 25. The slot 61 enables the screws to be fastened at various positions so that the finger may no adjusted at the height desired. This is an advantageous construction when it is desired to mold blocks of different sizes. The portion of the plate 25 carrying the member 59 extends beyond the plates 26 and 27 as shown at 62.

The operation of the machine is as follows: The cores having been withdrawn the mold is tilled to a level which corresponds to the lower edge of the cores in their raised position. The cores are raised by moving the lever 32, thus first raising the inner plate 25 and the upper sections of the cores. When the cores have been fully extended the lower end of this slot 35 engages the bolts 3% so that further movement of the lever 32 causes both the upper and lower sections to rise. lVhen the proper height has been reached, the hook 57 of the lever 15 engages the finger 59 and holds the plates and the cores in their raised and extended positions. The cores are then inserted into the mold which is filled with concrete or other material to the proper height. Upon the downward movement of the plunger the arm l i engages the upper end of the lever 15 and releases the hook 57 from the finger 59 so that as the plunger compresses the material in the mold the cores are free to contract telescopically and to move downward to their lowermost positions. The weight of the lever 32 and the friction between the several parts are sutficient to prevent a too sudden contraction of the cores.

After the plunger has been withdrawn and the mold removed to a convenient place, the cores are withdrawn by operating the pinion 22 and the mold box is taken apart to permit the molded block to be removed.

By operating in this manner, it will be seen that the material around the cores will have a greater tendency than heretofore to become uniformly compacted, giving a block of uniform strength throughout- Various changes and modifications may be made in the above-described apparatus without departing from the scope of our invention,

We claim:

1. A molding apparatus comprising a mold, and cores in said mold vertically extensible therein, said cores being adapted to gradually contract under the compression of the material in said mold.

2. A molding apparatus comprising a mold, and contractible cores in said mold adapted to yield appreciably to the pressure of the material being molded when said material is compressed.

3. A molding apparatus comprising a mold, cores in said mold vertically extensible therein, means for extending said cores, and a plunger for compressing the material in said mold, the pressure of said material causing said cores to contract during the compression stroke.

a. A molding apparatus comprising a mold, cores in said mold vertically extensible therein, means for holding said cores in an extended position, a plunger for compressing the material in said mold, and means for releasing said cores to permit them to contract under the compressing action of said plunger.

5. A molding apparatus comprising a. mold, cores in said mold vertically extensible therein, means for holding said cores in an extended position, a plunger for compressing the material in said mold, and means operated by said plunger when lowered for releasing said cores to permit them to contract under the compressing action of said plunger.

6. A molding apparatus comprising a mold, cores in said mold vertically extensible and vertically movable therein, means for extending and raising said cores, and a plunger for compressing the material in said mold, said cores being capable of contracting and lowering during the compressing action of said plunger.

7. A molding apparatus comprising a mold, cores in said mold vertically extensible and vertically movable therein, means for holding said cores in an extended and raised position, a plunger for compressing the material in said mold, and means operated by said plunger when lowered for re leasing said cores to permit them to contract and lower during the compressing action of said plunger.

8. A molding apparatus comprising a mold, cores in said mold movable vertically and comprising vertically telescoping sections, means for raising the upper sections with respect to the lower sections and for further raising both upper and lower sections, means for holding said cores in a raised and extended position, and means operated by the plunger when lowered for releasing said cores to permit them to contract and lower under the compressing action of the plunger.

9. A molding apparatus comprising a mold, vertically extensible cores in said mold laterally movable into and out of said mold and vertically movable therein, two

contiguous lining plates together surrounding said cores and vertically movable therewith, means for inserting and withdrawing said cores laterally through said lining plates, and means for extending said cores and for raising and lowering said cores and lining plates in said mold.

10. An apparatus of the nature described comprising a mold, cores in said mold vertically movable therein, vertically adjustable means for holding said cores in raised posi tion, a plunger for compressing the material in said mold, and means operated by said plunger for releasing said cores from their raised position when the plunger is lowered.

11. A molding apparatus comprising a mold, cores in said mold vertically extensible and vertically movable therein, vertically adjustable means for holding said cores in an extended and raised position, a plunger for compressing the material in said mold, and means operated by said plunger when lowered for releasing said cores to permit them to contract and lower during the compressing action of said plunger.

In testimony whereof we aifix our signatures.

WILLIAM GRAF. CHARLES F. NICKEL.

Test:

J. HARVEY KIMMEL.

Copies of this patent ma; be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

